The Art of War — themes & analysis

Chapter 3 states the doctrine plainly. There is a hierarchy of strategic options, ranked from highest to lowest: disrupt the enemy's plans before they can act on them; break apart his alliances; attack his army in the field; besiege his cities. Each step down the list costs more, achieves less, and forecloses more options. By the time one is besieging walls, one has failed at every higher level.

The position is the negation of the heroic conception of war that prevailed almost everywhere else in the ancient world. Sun Tzu has no interest in glory, no patience for the contest of champions, no respect for battle as the test of virtue. War is, on his account, the gravest matter of the state, costly past calculation, and the general's first duty is to win the war before the armies engage. The brilliant commander who wins with apparent ease earns no reputation for genius — because the ease was the result of preparation so thorough that the outcome was never in doubt.

The doctrine explains why the book has found readers beyond the military. The principle that the best victory is the one that does not require a fight has applications wherever there is conflict — in law, in negotiation, in commerce, in politics. Every reader who has found those applications has not been wrong to do so. The text was written for soldiers but the teaching was always more general: that the actor who wins by configuration rather than force has understood something the actor who wins by force has not.

What is often missed is the severity of the corollary. If the highest excellence is to win without fighting, then every battle fought is, by definition, a failure of the strategic ideal. Not a moral failure — Sun Tzu is not a pacifist — but an operational one. The general who had to resort to battle did not prepare well enough, did not read the situation clearly enough, did not configure his forces so that the outcome was inevitable before the first clash. The doctrine is not a counsel of avoidance. It is a counsel of preparation so thorough that avoidance becomes natural.

Where to follow it: Chapter 1 (planning and deception), Chapter 3 (the hierarchy of strategy), Chapter 6 (initiative and weak points), Chapter 13 (the closing manifesto).

Chapter 3 closes with the second-most-quoted passage in the book: "Know your enemy and know yourself, and you will win a hundred battles. Know yourself but not the enemy, for every victory gained you will also suffer a defeat. Know neither the enemy nor yourself, and you will lose every battle." The structure is exact and the implication is more demanding than usually noticed.

Self-knowledge is not, on Sun Tzu's account, automatic. The general is in danger of overestimating his own forces, his own discipline, his own reading of the situation. He is equally in danger of underestimating them — of failing to use the strengths he could be using if he saw them clearly. The discipline of self-knowledge is treated in the text with the same rigour as the discipline of intelligence about the enemy. Both are pursued through the same methods: observation, calculation, the slow patient assembling of information and the refusal of flattery.

Chapter 10 extends the principle. Knowing the enemy and knowing your troops is not enough: you must also know the terrain. "Know the enemy and know yourself, and your victory is certain. Know heaven and know earth, and your victory is complete." The command to know oneself therefore turns out to be a command to know one's entire situation — forces, terrain, weather, timing, the character of the enemy's commander. The general who has done this work will never be surprised. The general who has not done it has delegated the outcome to chance.

The doctrine has been read for centuries as the closest thing in military literature to the Delphic command to know thyself, and the parallel is not accidental — the Warring States philosophers were working on the same problem as the Greeks of the same period. What Sun Tzu adds to the philosophical tradition is the insistence that self-knowledge is a tactical asset. It is not wisdom for its own sake. It is the ground on which every other advantage rests. The general who has not done the work of self-knowledge cannot be trusted with the lives of his men.

Where to follow it: Chapter 3 (know the enemy and yourself), Chapter 4 (invincibility and vulnerability), Chapter 10 (terrain and self-knowledge), Chapter 13 (intelligence as the ground of action).

Chapters 4 and 5 introduce the most distinctive and influential idea in the treatise — the distinction between form (xing, the visible configuration of an army: its size, position, terrain, supply, and morale) and energy (shi, the kinetic force that surges through an army when its configuration is rightly matched to its situation). The distinction is easier to recognize in practice than to define in the abstract.

Sun Tzu's central image is the boulder on the mountain. The boulder sitting on the slope is form. The momentum it acquires when released is energy. The general's work is the work of configuration: to position his forces so that, when the moment comes, the energy the configuration releases is overwhelming. The victory does not happen in the battle. It happens in the preparation. By the time the armies meet, the outcome is already implicit in the form. The general who prepared well finds his troops moving almost by themselves, the boulder rolling. The general who prepared badly finds no amount of brilliance in the moment can repair the prior failure.

Chapter 5 extends this to the relation between direct and indirect methods. The direct approach is used to engage the enemy; the indirect is what delivers victory. The combinations of direct and indirect are as infinite as the combinations of five musical notes or five primary colors — the basic elements are few, but their interaction generates endless variety. A brilliant commander relies on the power of combined momentum, not on the heroics of individuals. He selects the right people and lets the momentum of the configuration carry them.

The doctrine has been one of the most influential in the history of strategic thought. Mao's protracted war theory is built on it. Liddell Hart, the British military theorist, credited the Art of War with the indirect-approach doctrine he had believed himself to be inventing. What the doctrine implies is that the general's preparation is more consequential than his command in action. The moment of battle is when the work is harvested, not when it is done.

Where to follow it: Chapter 4 (tactical dispositions), Chapter 5 (energy), Chapter 6 (weak points and initiative), Chapter 11 (the nine situations).

Chapter 1 states the principle that all warfare is based on deception. This is not a license for dishonesty in the ordinary sense. The deception in question is the manipulation of the enemy's perception so that he believes one is strong where one is weak, intends to attack where one plans to defend, is far away when one is near. The army that controls what the enemy believes controls the engagement before it begins.

Chapter 6, "Weak Points and Strong," is the operational extension of this doctrine. Its opening principle is about initiative: whoever arrives at the battlefield first and waits will be fresh; whoever arrives second and rushes into action will be exhausted. The general who can compel the enemy to come to him has imposed his will; the one who is compelled to go to the enemy is being commanded. The chapter that follows is a sustained meditation on this single point — how to choose the time, place, and form of engagement, and how to deny that capacity to the enemy.

The operational recommendations follow directly. Strike where the enemy is unprepared. Move where he does not expect. Attack what he must defend. Defend what he cannot attack. Avoid strength and strike at weakness. Concentrate your forces while the enemy must scatter his; then pit your whole against his parts. These formulations have been recognized for twenty-five centuries as among the most useful practical principles in the literature of conflict. They have outlasted the Warring States period because they are not specific to armies — they apply wherever there is an actor with limited resources deciding where to apply them.

Chapter 6 closes with an image that summarizes the whole doctrine. Military strategy is like water. Water naturally flows downhill, away from high ground. In war, the principle is the same: avoid the enemy's strength and strike at weakness. Water shapes its course according to terrain; the commander shapes his victory according to the enemy he faces. As water has no fixed shape, warfare has no fixed formula. The commander who can adapt tactics to match every enemy and still achieve victory is the one the book calls a genius.

Where to follow it: Chapter 1 (deception), Chapter 5 (energy and indirect methods), Chapter 6 (weak points and strong), Chapter 8 (variation in tactics).

Chapter 2 opens with a severe accounting. A major military operation — a hundred thousand soldiers, supply trains, conscription, disrupted agriculture — costs the state ruinously. The disruption at home may affect hundreds of thousands of households. To stake the outcome of all this on the day of battle, when the day's outcome could be tilted decisively by knowledge of the enemy's dispositions, is to be foolish past forgiveness. Speed is essential; a prolonged war exhausts the nation. No ruler has ever benefited from a protracted campaign.

Chapter 13 returns to the same calculation from the opposite direction. The maintenance of an army costs enormously. To economize on the recruitment and reward of spies — when the cost of intelligence is a tiny fraction of the cost of the army — is the worst false economy a sovereign can practise. The five types of spies: local (recruited from the population), inside (from the enemy's own officials), turned (enemy spies recruited to work for you), expendable (fed false information to leak to the enemy), and surviving (those who return with real intelligence). When all five types are working simultaneously, the system becomes what Sun Tzu calls the divine web, and the sovereign holds an impenetrable advantage.

The closing paragraphs of Chapter 13 step back from the particular doctrine of espionage and make the larger claim for the entire book. The wise sovereign and the able general win because they know what others do not. This knowledge cannot come from supernatural sources, from inference, from analogy, from divination. It can only come from people. The recruitment, treatment, and use of those people is therefore the ground on which everything else rests. The book that opened with the five factors of planning closes with the one factor the five factors all depend on: knowledge of the enemy's actual situation.

The reader who has read the book attentively recognizes this as a single argument across the thirteen chapters. The text — however many hands shaped it across however many generations — has the integrity of a single mind. The doctrine that opened with the highest excellence (to subdue the enemy without fighting) closes with the practical means by which the highest excellence is most often achieved: foreknowledge, and the intelligence apparatus through which foreknowledge becomes possible.

Where to follow it: Chapter 2 (the cost of war), Chapter 3 (strategic attack), Chapter 12 (the attack by fire — anger and restraint), Chapter 13 (the use of spies).